I was looking for an answer for this weird problem and I stumbled upon your Forum, so just wanted to start by saying Hi, and then tell you my problem which goes as follows:
At random intervals, this computer hangs and then the screen gets scrambled (I attached a screen shot). I tried replacing the RAM, the Graphics card, and the hard drive. And I know it is a hardware problem because it also happens during POST. Now I know it is probably the motherboard I just want to know exactly what is causing this problem.